Hi, my car is a 2002 Audi A4 1.8T AVJ. I started tuning it a few weeks ago and I've done over a dozen reflashes. The last thing I did was set ESCONF bit 3 from 30 to F0 (my rear O2 is disconnected) and KFNWSE to 18 in the whole map (switch off VVT in normal conditions). After the last flash the car worked fine. The next day it wouldn't start.

It just cranks on starter and it feels like there's no fuel or no spark. VCDS connects and there are no error codes. I tried cranking for over 10 seconds continuously and still nothing. I can hear the fuel pump working for a second or two when I turn the ignition key to ON. I did output test for injectors in VCDS and they seem to work. I still didn't check if there is any current after the ignition coils.

Strange thing is I tried starting with the MAF disconnected and there were no error codes in VCDS after that. My ESCONF bits are from 10D19 to 10D1F, which I'm not sure if it's right. I've set all the other maps for rear O2 delete except CWDLSAHK (I can't find it) in previous flashes and there were no problems. Maybe ESCONF isn't there and I set something else... There are no checksum errors in the file I flashed. I'm afraid to flash the original version because I don't have enough power in the battery anymore, but I will buy a charger if I need to write the ECU.

I'm attaching my current tune and the original. The ECU is 8E0906018B, HW 0261206868, SW 1037360990.

Please, help.

Thanks for your reply. I didn't flash the original because my battery is almost dead. I wanted to know if ESCONF bits are there where I wrote above, before I suspect the file and buy a battery charger. My file had no errors and the last writing to ECU was fine. Car started fine and I made more than 20 miles including another couple of engine stop-start. But maybe that's silly, I'll just go buy a charger and flash the original file just to exclude that issue...

P.S. I also need to see if there is some module between the ECU and the coils and check if it's OK, because I had (rarely) starting issues even before I started tuning. The difference is the car started after 6-10 sec cranking and now it doesn't start at all.

Yes, it could be those too. But can a file without checksum errors and with a successful flash cause these symtoms?

Coldstart routine? Might a faulty sensor thro it off?

After the writing finished, nefmoto flasher disconnected, I waited about 5 sec (like I always did), turned ignition on and the car started fine. It worked fine for over 20 miles. I parked it and the next day (20 hours later) it wouldn't start.

It won't start when I clear the codes and there were no codes after that, which is strange to me. I disconnected the maf and radiator fans while ignition on, but no fault codes in VCDS.

Now I remember that some time ago (I had starting issues occasionally) I saw an Engine Speed Sensor error (intermittent) in VCDS (along with EPC lamp lit). I'll buy the sensor tomorrow and see if it'll start.

Thanks, I'll try that tomorrow. By reflash you mean normal reflash (not in boot-mode)?

Hi, I charged the battery and successfully wrote the original file to the ECU. But it wouldn't start. I used argdub's tool to read via OBD and I attach the file. No errors in VCDS.

I lol'd when I saw that you have flashed this car 43 times.

I have nothing to add to your issue though